Plattnerite Pbo2 C 2001-2005 Mineral Data Publishing, Version 1 Crystal Data: Tetragonal
Plattnerite PbO2 c 2001-2005 Mineral Data Publishing, version 1 Crystal Data: Tetragonal. Point Group: 4/m 2/m 2/m. Commonly as crystals, prismatic k [001], showing {010}, {011}, {110}, {131}, {001}, to 5 mm; may be nodular or botryoidal, fibrous and concentrically zoned, massive. Twinning: On {011}, as contact and penetration twins, rarely polysynthetic. Physical Properties: Tenacity: Brittle. Hardness = 5.5 D(meas.) = 9.564 D(calc.) = 9.563 Optical Properties: Opaque to slightly translucent. Color: Jet-black, iron-black, brownish black; yellowish in transmitted light; gray-white in reflected light, with red-brown internal reflections. Streak: Chestnut-brown. Luster: Bright metallic to adamantine; tarnishing dull on exposure. Optical Class: Uniaxial. Pleochroism: Distinct. n = 2.30(5) Anisotropism: Noticeable; midnight-blue. R1–R2: (400) 18.5–21.3, (420) 18.4–21.9, (440) 18.5–21.5, (460) 18.5–20.2, (480) 18.5–19.8, (500) 18.4–19.4, (520) 18.2–18.9, (540) 17.9–18.4, (560) 17.5–18.0, (580) 17.0–17.4, (600) 16.5–16.9, (620) 16.0–16.4, (640) 15.5–15.9, (660) 15.0–15.4, (680) 14.4–15.0, (700) 14.0–14.5 Cell Data: Space Group: P 42/mnm. a = 4.9525(4) c = 3.3863(4) Z = 2 X-ray Powder Pattern: Ojuela mine, Mexico. 3.500 (100), 2.793 (94), 1.855 (80), 2.469 (40), 1.524 (23), 0.823 (20), 1.568 (19) Chemistry: (1) PbO2 99.6 CuO 0.1 Total 99.7 (1) Ojuela mine, Mexico; by electron microprobe.
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